Do amp design give a different sound?

Rick84

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Just a general question out of interest,

Possibly a stupid question to someone in the know but amp designs sound different? A/B, class D etc.
 
An interesting question, I honestly have no idea.
 
Subtly so depending how hard you drive them, what speakers, what sound level you listen to, etc.
 
Personal opinion, yes.
For example, I find a number of Naim amps to "enhance" certain frequencies, resulting in a more bouncy and fun presentation style. Doesn't IMO sound as neutral as some other amps, and clearly some people love it.
Additionally, some amps are more technically suited to say driving low impedence speaker designs than others.

Either way, my view is that the right approach is to find a pair of speakers that you like and work with your room, THEN find an amp best suited to work with the speakers in question. All this talk of "best whatever" by certain magazines is just a waste of rhetoric and the relevance is one of their opinion, their room and the speakers they're using. Synergy with what you're actually using is far more important.
 
It got me thinking because i know some pple like Pioneer's class D amplification with KEF's r series. I had a CA 751r which uses the A/B design which i found to be a very potent combination.

I was just curious as to whether the design of the amp made a difference to the characteristics of the sound. More laid back, open sound, more direct, ect.
 
IMO, it comes down to dynamics and the way that the amp responds to the more lively bits - and that comes down to the power supply as much as the output stage.

Class D amps use very heavy filtering to turn the basic On-Off nature of the output stage into an acceptable audio signal. To my ears, they never sound as full bodied as a conventional Class A/AB amps, particularly when driven hard.

Power Supplies: Linear power supplies need to be very large to prevent excessive ripple at times of heavy demand and to allow the supply to recover quickly. The large transformer gives a low source impedance and this seems to be what gives them the solidity that can be missing from amps with under rated supplies. Switch Mode Power Supplies also need to be adequately rated, as they tend to suffer from rail sag and quite nasty artifacts on the supply rails.

Years ago, my first job from college was designing, building and testing all sorts of interesting audio and analogue computer equipment, including huge linear power supplies - 5V @ 500A, that sort of thing! We designed and built an instrument grade power amp which gave a flat response which did not change within the rated load and power. This was a conventional class A amp with a massive power supply - way beyond what the output devices could ever have demanded. The result was an amp that had an excellent performance on paper, but sounded, well, OK!! We all felt it lacked bass and sounded quite flat, even when pushed hard. When we compared a similarly rated PA amp - about 150W as I remember, it sounded much more punchy, but we found that the supply rails would modulate to the beat - increasing clipping, and the bass had a lift of a few db as well.

So in conclusion, a well designed power amp should be transparent, but in practice, designers will normally tweak the design, either to enhance the sound or to reduce the budget! Quite a lot of current budget AVRs use some form of Class D, as it is more efficient, so a smaller power supply can be used and less heat will be generated. If you think that many amps have 100W per channel with 7 channels available, but a PSU capable of maybe a few hundred watts! When driven hard with heavy action scenes, or when Bi-Amping is used, the PSU is heavily stressed and the amp changes in sound character.
 
WOW,

Im gunna re read and digest this in the morning when the Vodka is out my system lol.
 
Yes would be my answer,
As much as I would like to agree that they should be transparent as said above, I found there seem to be a 'in house sound' with the amps I have had but it also to with pairing with the right speakers.

For instance I had a Marantz amp with Wharfedale speakers in my dining room for a few years and was very happy with the sound from that combo but change the amp to a naim unitiqute and the sound became woolly. The speaker position is far from ideal sitting in ikea shelving units but have no choice but to work with that. It's not bad but not as good as it can be. Still, Same speakers in same position sounded more defined with the Marantz .

I also find Nad amps sounded different as the vocals were more predominant than with Marantz or my old Albarry amp I had.
 
That is the hardest part of the question, as not many manufactories make amps using different techs, so it's difficult to know if its the system that is causing the sound or the 'in house sound'.

I guess the only way is to look at something from the AVR makers, since as stated they tend to do class D at cheap level and A/B at higher prices. But again your not comparing like for like, higher price amps should sound better or your throughing your money away.
 
If there's an "in house sound" then it comes by design and by doing something/altering/colouring/boosting the signal passing through the amp. That could be something as simple as boosting bass or treble frequencies. Any amp manufacturer that deliberately sets out to do this cannot claim to be making a High Fidelity product as by definition, they are altering the fidelity of the signal. Now some people may prefer the resulting sound and I've no issue with that but it can't be claimed to be Hi-Fi.

Beyond that scenario, all Hi-Fi amps running within their design parameters and not distorting or clipping should sound pretty similar assuming you're not putting too heavy a load on them speaker wise.
 
If there's an "in house sound" then it comes by design and by doing something/altering/colouring/boosting the signal passing through the amp. That could be something as simple as boosting bass or treble frequencies. Any amp manufacturer that deliberately sets out to do this cannot claim to be making a High Fidelity product as by definition, they are altering the fidelity of the signal. Now some people may prefer the resulting sound and I've no issue with that but it can't be claimed to be Hi-Fi.

Beyond that scenario, all Hi-Fi amps running within their design parameters and not distorting or clipping should sound pretty similar assuming you're not putting too heavy a load on them speaker wise.

I like the theory but in practice all amps have an in hosue sound, all the way up to the real high end.

I think it is just not possible to produce an entirely neatural amp and therefore they have to make choices on what parts of the sound is more important and focus on getting the most out of that part.
 
If there's an "in house sound" then it comes by design and by doing something/altering/colouring/boosting the signal passing through the amp. That could be something as simple as boosting bass or treble frequencies. Any amp manufacturer that deliberately sets out to do this cannot claim to be making a High Fidelity product as by definition, they are altering the fidelity of the signal. Now some people may prefer the resulting sound and I've no issue with that but it can't be claimed to be Hi-Fi.

Beyond that scenario, all Hi-Fi amps running within their design parameters and not distorting or clipping should sound pretty similar assuming you're not putting too heavy a load on them speaker wise.

There is no agreed upon standard for Hi Fi and all attempts to introduce one have been vigorously resisted.

Yes, with theoretical design practices adhered too all amps not overdriven " should" sound similar, but no one is doing this, in fact , in these days of custom Asics and house tuning no one is even using the same parts for any class of amplifier design.

Basically , you would be hard pressed to find any two amps from any two major manufacturers that sound the same these days. Almost all have some kind of signature sound.
 
I think its not in the industries interest to create a standard sound, as then people would just be buying based on design of the casing and not because they like the sound of a specific brand over another.
 
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take this thread over to avs lol
 
Have there been any well designed research studies that have conclusively demonstrated differences between amplifiers in their "in house" sound? I guess such studies would hath to have good internal validity (blind administration, large enough samples to detect subtle differences, etc.) but also good external validity (real life conditions, rather than artificial laboratory ones).

That's not to say that personal experience is entirely worthless.

From my own limited experience and from what I've read, I get the impression that there is more difference between preamps than that it is between power amps.

In today's digital world I think I would rate the preamp has being more important than the source, and second only to speakers, when investing money into trying to achieve a good sound.
 
There is no agreed upon standard for Hi Fi and all attempts to introduce one have been vigorously resisted.

Yes, with theoretical design practices adhered too all amps not overdriven " should" sound similar, but no one is doing this, in fact , in these days of custom Asics and house tuning no one is even using the same parts for any class of amplifier design.

Basically , you would be hard pressed to find any two amps from any two major manufacturers that sound the same these days. Almost all have some kind of signature sound.

My point is if you, as a manufacturer, deliberately set out to boost a part of the signal then you can't call it HiFi. There are some amps that measure flat across the audible range and it's not beyond difficult to do in this day and age.

Who are the people resisting standards for High Fidelity anyway? Work that out and you may deduce their motives.
 
My point is if you, as a manufacturer, deliberately set out to boost a part of the signal then you can't call it HiFi. There are some amps that measure flat across the audible range and it's not beyond difficult to do in this day and age.

Who are the people resisting standards for High Fidelity anyway? Work that out and you may deduce their motives.

But you can call it Hi Fi, thats my point. You can call anything you want Hi Fi because there is no official standard and no definition of that that term to be measured against.
Every " Hi fi" manufacturer resists a standard because it limits what they can market or sell.

I agree that the response should be flat across the audible range, thats what "should" be a feature of a good system and thats what i always look for, but until that becomes a standard then its effectively just idealism.

These days there are known and very popular companies that go out of their way to avoid a flat response and call it a signature sound. Beats for example have a 6db boost across the lower end... They sell as a premium brand.

Not everyone is as extreme as that, but this is the problem in the audio industry these days. Marketing and Hype determine what sells, not performance, and as such, hardly anyone is aiming for what "should" be the best performance, instead they sell awful products with high value and "hip" trademarks.
It would seem that having the correct logo on show is what sells.

If there was a standard whereby reviewers could say, "this is what should be happening and this unit is failing miserably", then half of these companies would be gone.
They all know this of course, which is why they all resist it so much, they could no longer throw together cheap nasty materials in an underperforming unit, stick it in a fancy cardboard box and market it as a premium product.
 
Also flat is only part of the story, as is shown from the current rethinking about the cinema standards. It's perfectly possible to get a flat response from one set of data (pink noise in the cinema perspective) but it doesn't result in a good sound in practice. I am very glad that the music i listen too isnt' a test tone.
 
But you can call it Hi Fi, thats my point. You can call anything you want Hi Fi because there is no official standard and no definition of that that term to be measured against.
Every " Hi fi" manufacturer resists a standard because it limits what they can market or sell.

I agree that the response should be flat across the audible range, thats what "should" be a feature of a good system and thats what i always look for, but until that becomes a standard then its effectively just idealism.

These days there are known and very popular companies that go out of their way to avoid a flat response and call it a signature sound. Beats for example have a 6db boost across the lower end... They sell as a premium brand.

Not everyone is as extreme as that, but this is the problem in the audio industry these days. Marketing and Hype determine what sells, not performance, and as such, hardly anyone is aiming for what "should" be the best performance, instead they sell awful products with high value and "hip" trademarks.
It would seem that having the correct logo on show is what sells.

If there was a standard whereby reviewers could say, "this is what should be happening and this unit is failing miserably", then half of these companies would be gone.
They all know this of course, which is why they all resist it so much, they could no longer throw together cheap nasty materials in an underperforming unit, stick it in a fancy cardboard box and market it as a premium product.

The charlatans should not be allowed to define what is Hi-Fi anymore than criminals should be allowed to define the law.

There may not be an official standard but why is that? It's because those companies who would fail to meet high standards refuse to agree because they know they would fail to meet it. But any discerning consumer in this area should know what High Fidelity should mean. It should mean an amplifier manufacturer not setting out to deliberately alter the signal.
If amp makers want to have a 'house sound' then put it at the end of a switch so when the switch is off you get a flat response, when you flick the switch, you get the house sound. But altering bass by 6db then selling it as high fidelity is lies.

Because we have these cowboys refusing to allow standards to be set, ordinary customers up and down the land are being sold snake oil disguised as technical specs.

So I come back to the idea that it should not be the manufacturers who set the standard but an independent group should be set up to take evidence from all interested parties and then make recommendations for what standards should be met before something is termed 'Hi-Fi'. This would then be enshrined in legislation.
 
I think there will always be an, "in house sound",because to a certain extent, making great hi fi is an artists job, as well as a technicians.
Because human ears are not measuring instruments, our perception of hi fi is different for everybody, because we bring ourselves to the experience. Hi fi could be made perfect on paper as noiseboy72 pointed out, but sounds terrible to the ear,. This where the expertise comes in, to paint enough warmth onto the soundstage, that tinges the cold clarity with an image we can recognise, that's the trick of it.
 
The topology matters. Then how they are tweaked. Amplification introduces distortion. Its how they manage that. Also how clipping is managed.

Agree Class Ds sound a bit "dead". Too much filtering. But to be fair, that's really the B&O ICE module based ones. Primare sound pretty good.

Arcams are known for a more subtle, subdued sound. Naims are heavier. Linns fleet-footed.

Read somewhere that amps are tuned for the market's ears, which are influenced by the spoken language. Hence Jap amps sound harsh compared to European. Americans are just loud and bold.

Canadian amps are seen as a good compromise.
 
A flat response isn't always something that sounds good or the way you actually like a sound to be played / heard!! Its just a starting point..................Hifi is usually determined by primarily cost as something that costs 10k / silly amount of money is automatically accepted as sounding better than 3k but i guess its all subjective and relative.

You can through top note kit together but as we know it doesn't guarantee good sound or a sound that you like , and as already stated this is mainly down to manufacturers deciding on which characteristics / road they want to drive down..............As far as d class in concerned which is still in its infancy compared to other forms / topologies , imo i think that we / manufacturers will all be heading down the same road as the technology matures and develops.

As for d class pulling back on power when pushed is something most amps will do if 1/ they have a built in circuit to do so or 2/ is incorrectly picked for the job in hand and a much too higher load is presented...........It all reminds me of when turbo diesel car entered into the arena and most people claimed they were to noisy dirty and slow but look where they are now.



P.S Who ever thought 25 years ago that diesel fuel would cost more than petrol:rolleyes:
 
I think there will always be an, "in house sound",because to a certain extent, making great hi fi is an artists job, as well as a technicians.
Because human ears are not measuring instruments, our perception of hi fi is different for everybody, because we bring ourselves to the experience. Hi fi could be made perfect on paper as noiseboy72 pointed out, but sounds terrible to the ear,. This where the expertise comes in, to paint enough warmth onto the soundstage, that tinges the cold clarity with an image we can recognise, that's the trick of it.

That should all be done at the content mastering stage, the process of getting what you want onto the disc or medium of choice.
This is what recording studios, mixing desks and sound engineers are for.

The job of Hi Fi or high fidelity equipment, " should" be to reproduce that signal from the medium as faithfully as possible.
When you have equipment that boosts the lower end by 6db , or alters the material in any significant way, that artistic intent in the studio is destroyed.

Try listening to some Rock, Classical, or Jazz on Beats Equipment...truly truly awful.
 
That is way when cd first arrived every one thought that they were so crystal clear until we found out that the top and bottom ends of the frequencies were being chopped to give less distortion.
 
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